Question

我正在尝试将一些C＃代码转换为VB .Net，并且遇到了一些delgate转换问题。

BackupLibraries.cs

Public Class Backup
{
public event EventHandler<BackupPEventArgs> Backup;

...
if (BackupProgress != null) BackupProgress(this, new BackupProgressEventArgs(percent_complete))
...
}

public class BackupEventArgs : EventArgs
    {
        private float percentage;

        public BackupProgressEventArgs(float percentage)
        {
            this.percentage = percentage;
        }

        public float Percentage
        {
            get { return percentage; }
        }
    }

UnitTest.cs

public void BackupTest()
{
Backup bu = new Backup()
        bu.BackupProgress += delegate(object sender, Backup.BackupEventArgs e)

        {
            Debug.WriteLine("Percentage: " + e.Percentage.ToString());
        };
}

它正在转换sb.Backup + = delegate（对象发送者，SQLBackup.BackupProgressEventArgs e）并将其连接到我遇到问题的其他课程中。

在VB中：

Backuplibraries.vb

Public Class Backup

Public Event Backup As EventHandler(Of BackupEventArgs)

...
RaiseEvent Backup(Me, New BackupEventArgs(percent_complete))
...
End Class

Public Class BackupEventArgs
            Inherits EventArgs

UnitTest.vb

Public Class BackupTest

Dim bu As New Backup()

bu.BackupProgress = Sub(sender As Object, e As BackupEventArgs)
                         Debug.WriteLine(e.Percentage.ToString())
                         End Sub

End Class

当然

bu.BackupProgress = Sub(sender As Object, e As BackupEventArgs)
                             Debug.WriteLine(e.Percentage.ToString())
                             End Sub

是我从C＃转换为.Net的问题所在。

Answer 1

您可以在这里尝试AddHandler

<击>

AddHandler bu.BackupProgress, AddressOf Sub(sender As Object, e As BackupEventArgs)
                         Debug.WriteLine(e.Percentage.ToString())
                         End Sub

<击>

要让参数进来，这将无法在VB.Net中以这种方式保持匿名。您需要使用固定地址抽象出您的方法。

Protected Sub BackupProgressDelegate(sender as Object, e as BackupEventArgs)
    Debug.WriteLine(e.Percentage.ToString())
End Sub

...

AddHandler bu.BackupProgress, AddressOf BackupProgressDelegate

委托将C＃转换为VB

1 个答案: